Mount Agung’s Calmness Yields Two Scenarios

JAKARTA, NNC – Sutopo Purwo Nugroho, Head of Data and Information Center and Public Relations of National Disaster Management Agency (BNPB), has reported that Mount Agung visually looks calm. The volcanic earthquakes occur superficially and the measured SO2 gas has dropped dramatically.

According to data from the Meteorology, Climatology and Geophysics Agency (BMKG) delivered by Sutopo, the SO2 gas measured drastically decreased in concentration compared to the explosive eruption phase on 26-27 November. Even today its value is 20 times lower.

"This condition causes two possibilities. First, the magma that rises to the surface of its speed weakens because the energy loss due to magmatic gas has diminished after the eruption of yesterday and finally runs out, to its equilibrium. Secondly, there is a possibility of clogging of the magma pipe, the magmatic fluid moving to the surface is blocked by the lava on the cooled and hardened surface, "explained Sutopo during a press conference at the BNPB office on Tuesday (5/12/2017).

Sutopo said, if the first possibility happens then the potential for eruption will decrease due to loss of mobility. Even further eruptions may become unobserved in the near future until someday reborn.

In addition, the potential for eruption will increase as the accumulation of magma pressure increases. At certain times, when the lava yag covers the magma out, its strength is lower than the pressure accumulated beneath which eruption can occur.

Whereas if the second possibility occurs, that is, if there is a blockage and in a long calm period then the possibility of accumulation of pressure is greater, the eruption lets happen more explosive from yesterday's eruption. As in the last 1963 eruption, there was a resting phase for two weeks before a major eruption reached 23 km.

"But, if the calm period is short then the possibility of accumulation of pressure is not great, the eruption makes it possible to happen with an explosion similar to yesterday's eruption or lower than the main eruption in 1963," explained Sutopo.